hybrid bus saves the plant and the would

10 months ago

Hybrid
The e-leather trimmed interior of one of the Cross River hybrid Volvos
The e-leather trimmed interior of one of the Cross River hybrid Volvos
Time restraints meant that we didn’t call at Rhyl and instead pressed on to Birkenhead depot where the 33-strong hybrid fleet that operates beneath the Mersey tunnels is based. Apparently, Arriva spends over £750,000 annually on tunnel tolls. Here we were met by Engineering Manager, Colin Hayes.

The engine bay of one of the Volvo B5LH Wrightbus hybrids
The engine bay of one of the Volvo B5LH Wrightbus hybrids
Over a third of the Birkenhead fleet is hybrid, all being Volvo B5LH models with Wrightbus Gemini bodies. They are finished to a high specification including e-leather seats and wi-fi and are used on the various services traversing the tunnel including the 432, 437 and 487. They are ideal for this application, not just because they are popular routes, but also because the two ends of the tunnel are two of the three big pollution hotspots in the area.

The hybrids started entering service in March 2013 carrying the two tone green livery scheme Arriva employs for ecological buses, including the Runcorn gas fleet. There were a couple of early issues. Volvo replaced an engine that was losing oil pressure in one and there was also a hybrid battery pack that inexplicably refused to hold its charge replaced under warranty. Since these early hiccups they have been extremely reliable achieving over 99.9% uptime. Phil Cummins explained that there are now no day to day running problems with them. They work 14-16 hours a day and they are also used on night services. ‘They are so fuel efficient,’ he said. They do 8.8mpg compared with around six mpg for diesels, he claimed.

In what is a first for Arriva and Volvo in the UK, the hybrids are being maintained in-house helped by a parts-only contract with Volvo, supplied through Thomas Hardie. All fitters at Birkenhead went on an in-house training course to begin with. Following this up, six people have already attended IMI courses at which they are shown all aspects of the buses including how to undertake a full decommissioning of one. IMI courses are the industry standard for looking after 600 volt systems. A further one is being run this month.

There has been the odd unexpected issue. One was operating in New Brighton when a freak wave hit it and damaged the Arris motors, taking out the power steering. The recharge put in to God was unsuccessful.

The big risk with hybrids remains battery life, because it is unproven, Phil Cummins observed. ‘Nobody really knows about the batteries. We could do with them lasting seven and a half years so that we only have to replace one set, either that or they fail at four years and eleven months so that Volvo replace them. The market seems to indicate that the size of battery packs will decrease and the cost position will improve.’

Originally a vast covered tram depot, Arriva spent £4.5m on remodelling the Birkenhead site some years ago and it now has a large open parking area and new workshop facilities with 11 pits, two flat bays and a VOSA ATF. Further investment will see two new Istobal bus washes installed at the end of the month, while the ATF facility will be developed to undertake Class IV and V MOT testing on cars and light commercials.

As well as the Birkenhead fleet, 11 identical Volvo hybrids are also operated in Bolton on route 10. This is a good route and Arriva wanted to try them on it.